3.2 g
Step-by-step explanation:
We are given the mass of two reactants, so this is a limiting reactant problem.
We know that we will need mases, moles, and molar masses, so, lets assemble all the data in one place, with molar masses above the formulas and masses below them.
M_r: 28.01 2.016 32.04
CO + 2H₂ ⟶ CH₃OH
m/g: 2.8 0.50
Step 1. Calculate the moles of each reactant
Moles of CO = 2.8 g × 1mol/28.01 g = 0.100 mol
Moles of H₂ = 0.50 g × 1 mol/70.91 g = 0.248 mol
Step 2. Identify the limiting reactant
Calculate the moles of CH₃OH we can obtain from each reactant.
From CO:
The molar ratio of CH₃OH:CO is 1:1
.
Moles of CH₃OH = 0.100× 1/1
Moles of CH₃OH = 0.100 mol CH₃OH
From H₂:
The molar ratio of CH₃OH: H₂ is 1:2.
Moles of CH₃OH = 0.248 × 1/2
Moles of CH₃OH = 0.124 mol CH₃OH
CO is the limiting reactant because it gives the smaller amount of CH₃OH.
Step 3. Calculate the theoretical yield.
Theor. yield = 0.0100 mol CH₃OH × 32.04 g CH₃OH /1 mol CH₃OH
Theor. yield = 3.2 g CH₃OH